[GH #962] more cpu types (bsd, cygwin, solaris, win32, darwin)

Tested ok on cygwin, solaris, win32, darwin-x86 and darwin-ppc.
FWIW: Solaris on QEMU prints QEMU Virtual CPU version 1.1.2, different to the other VMs
/usr/bin/kstat -m cpu_info | grep implementation would print the parent CPU type:
x86 (GenuineIntel 623 family 6 model 2 step 3 clock 2793 MHz)